Zds2p regulates Swe1p-dependent polarized cell growth in Saccharomyces cerevisiae via a novel Cdc55p interaction domain

• Published in: Molecular biology of the cell 2010-12, Vol.21 (24), p.4373-4386
• Main Authors: Yasutis, Kimberly, Vignali, Marissa, Ryder, Matthew, Tameire, Feven, Dighe, Shubha A, Fields, Stanley, Kozminski, Keith G
• Format: Article
• Language: English
• Subjects: Adaptor Proteins, Signal Transducing - genetics; Adaptor Proteins, Signal Transducing - metabolism; Amino Acid Sequence; Cell Cycle Proteins - genetics; Cell Cycle Proteins - metabolism; Conserved Sequence; G2 Phase; Gene Deletion; Mitosis; Mutation, Missense; Phosphorylation; Protein Interaction Mapping; Protein Phosphatase 2 - genetics; Protein Phosphatase 2 - metabolism; Protein-Tyrosine Kinases - genetics; Protein-Tyrosine Kinases - metabolism; Recombinant Proteins - genetics; Recombinant Proteins - metabolism; Saccharomyces cerevisiae; Saccharomyces cerevisiae - cytology; Saccharomyces cerevisiae - genetics; Saccharomyces cerevisiae - growth & development; Saccharomyces cerevisiae - metabolism; Saccharomyces cerevisiae Proteins - genetics; Saccharomyces cerevisiae Proteins - metabolism; Temperature; Time Factors
• ISSN: 1059-1524; 1939-4586
• DOI: 10.1091/mbc.E10-04-0326

Deletion of the paralogs ZDS1 and ZDS2 in the budding yeast Saccharomyces cerevisiae causes a mis-regulation of polarized cell growth. Here we show a function for these genes as regulators of the Swe1p (Wee1p) kinase-dependent G2/M checkpoint. We identified a conserved domain in the C-terminus of Zds2p consisting of amino acids 813-912 (hereafter referred to as ZH4 for Zds homology 4) that is required for regulation of Swe1p-dependent polarized bud growth. ZH4 is shown by protein affinity assays to be necessary and sufficient for interaction with Cdc55p, a regulatory subunit of protein phosphatase 2A (PP2A). We hypothesized that the Zds proteins are in a pathway that negatively regulates the Swe1p-dependent G2/M checkpoint via Cdc55p. Supporting this model, deletion of CDC55 rescues the aberrant bud morphology of a zds1Δzds2Δ strain. We also show that expression of ZDS1 or ZDS2 from a strong galactose-inducible promoter can induce mitosis even when the Swe1p-dependent G2/M checkpoint is activated by mis-organization of the actin cytoskeleton. This negative regulation requires the CDC55 gene. Together these data indicate that the Cdc55p/Zds2p module has a function in the regulation of the Swe1p-dependent G2/M checkpoint.